The present invention relates generally to a conveyer device and, more particularly, to a conveyer device for bookbinding machines having a number of processing stations and having plate or cleated chains or the like which take over book blocks and convey them intermittently to the processing stations. The plate or cleated chains are driven in a circulating manner and have chain beams that act in opposing directions to one another and have longitudinal bearers and longitudinal guides on which the strands of the plate or cleated chains are supported.
Bookbinding machines having processing stations for functions such as aligning and preforming, rounding-off and pressing, gluing and gauzing, gluing, book backing and headbanding and the casing of book blocks into book covers, are commonly known. Plate or cleated chains or side-bar chains are used for intermittently conveying the book blocks to the individual processing stations. By way of an example, German Patent Specification 24 28 620 describes a side-bar chain having an endless roller chain which is driven by chain wheels and on the chain pins of which there are located side bars which are mounted in an articulated manner by means of side-bar-holders. The side-bar chains are supported on longitudinal guides by carrying parts which are not illustrated. The distance of the side-bar chains from one another can be adjusted in a manner corresponding to the thickness of the book blocks in order to convey the latter in a straight line in a firmly clamped-in manner.
An object of the present invention is to provide a conveyer device for bookbinding machines having plate or cleated chains, or similar conveyer means, wherein the distance between the plate or cleated chains or the like automatically adjusts itself to the thickness of the book blocks while providing optimum gripping force and shortening set-up time. The timed positioning stroke of the plate or cleated chains may also be adjustable.
This is achieved in accordance with an embodiment of the invention in a simple and economical manner by varying the distance of the chain beams of the plate or cleated chains from one another through a setting drive via setting members for the purpose of adapting to different thicknesses of book blocks. The thickness of a book block may be automatically determined in the setting up operation during the continuous delivery of the book blocks via a measuring arrangement in the intake. The thickness of a book block is communicated directly to the setting drive as a reference value for the setting members for varying the distance between the chain beams via a memory-programmable control system.
According to a particular embodiment of the present invention, the processing stations are disposed at a defined timed distance from one another which may reflect a particular time based on a particular speed and distance. The plate or cleated chains can be driven intermittently, in a manner corresponding to the time, by a positioning drive having a positioning stroke, and the positioning stroke can be adjusted in a manner corresponding to an elongation of the plate or cleated chains as a result of wear.